As Orlove noted, barter may occur in commercial economies, usually during periods of monetary crisis. During such a crisis, currency may be in short supply, or highly devalued through hyperinflation. In such cases, money ceases to be the universal medium of exchange or standard of value. Money may be in such short supply that it becomes an item of barter itself rather than the means of exchange. Barter may also occur when people cannot afford to keep money (as when hyperinflation quickly devalues it).
I like to think of all of this as a noble expression of solidarity, as evidence of the decency of my fellow caraquenos at a time of mind-numbing shortages of basic goods and exploding inflation. I know that in most cases the motivation is necessity, even desperation. But that’s all right. Handing that freshly baked baguette to the parking lot attendant made both of us smile, even if for just a second.
Corporate barter focuses on larger transactions, which is different from a traditional, retail oriented barter exchange. Corporate barter exchanges typically use media and advertising as leverage for their larger transactions. It entails the use of a currency unit called a "trade-credit". The trade-credit must not only be known and guaranteed, but also be valued in an amount the media and advertising could have been purchased for had the "client" bought it themselves (contract to eliminate ambiguity and risk).
Barter is a system of trade in which one party exchanges products, goods and services in order to obtain required products, goods and services possessed by another. In a barter system, no money exchanges hands between the buyer and the seller. Instead, both parties to the sale determine how much of a product a fair trade for another product or service. Since people assign different worth to different products, a barter system makes it difficult to decide how much of an item needs to be offered for another for the transaction to become a fair trade. Barter system was largely used long ago before the world developed the concept of currency for the exchange of goods. Nevertheless, the barter system is still prevalent today among nations, corporations, companies, individuals and businesses. The barter system makes trade easier for countries that experience large volatility in currency conversion and for countries that do not have sufficient financial resources, but have large volumes of commodities that can be traded for other commodities.
Bartering is based on a simple concept: Two individuals negotiate to determine the relative value of their goods and services and offer them to one another in an even exchange. It is the oldest form of commerce, dating back to at time before hard currency even existed. (Learn more about how bartering evolved, read The History of Money: From Barter To Banknotes.)
The Buy-day (Wheat) Ecological Life Associate summarizes a vision of life in Gezi as follows: "In our world, which is being poisoned and destroyed by consumer culture, we need sustainable and self-operating models of lifestyles, including a barter economy, ecological food production, arts and craftsmanship based on needs, renewable and effective energy use, agricultural models backed by society, permaculture, slow cities, transitional towns, eco-villages, district gardens and secondhand and recycling systems.
Economic historian Karl Polanyi has argued that where barter is widespread, and cash supplies limited, barter is aided by the use of credit, brokerage, and money as a unit of account (i.e. used to price items). All of these strategies are found in ancient economies including Ptolemaic Egypt. They are also the basis for more recent barter exchange systems.